Perhaps you should try some spelling variations:
"thu sach ki thuat o khi" » "thuat sach ki thuat o khi", "thuoc sach ki thuat o khi", "thu hoach ki thuat o khi", "thu sach ky thuat o khi", "thu sach kinh thuat o khi", "thu sach bai thuat o khi", "thu sach kem thuat o khi", "thu sach ki thuat do khi", "thu sach ki thuat co khi", "thu sach ki thuat bo khi"
"tu bac ve thuc bai khi" » "tu bac ve thuc tai khi", "tu bac ve thuc ban khi", "tu bac ve thuc thai khi", "tu bac va thuc bai khi", "tu bac ve thuc bai thi", "tu bac ve thuc bai choi", "tu ban ve thuc bai khi", "tu cac ve thuc bai khi", "tu bat ve thuc bai khi", "tu bao ve thuc bai khi", "tu bac le thuc bai khi"
"tu sach y thuat bo chi" » "tu sach y thuat bao chi", "tu sach y thuat do chi", "tu sach y thuat co chi", "tu sach ky thuat bo chi", "tu sach my thuat bo chi", "tu sach kxy thuat bo chi", "su sach y thuat bo chi", "te sach y thuat bo chi", "tu cach y thuat bo chi", "tu sach y thuat ho chi", "tu sach y thuat bo cai"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("thu sach ki thuat o khi") or ((("tu sach y thuat bo chi") or ("tu bac ve thuc bai khi"))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("thu sach ki thuat o khi") OR ((("tu sach y thuat bo chi") OR ("tu bac ve thuc bai khi")))).
• Removing quotes may allow a broader search: (( thu sach ki thuat o khi ) or ((( tu sach y thuat bo chi ) or ( tu bac ve thuc bai khi )))).
• Adding a wildcard symbol may retrieve word variants: (("thu sach ki thuat o khi") or ((("tu sach y thuat bo chi") or ("tu bac ve thuc bai khi"))))*.