Perhaps you should try some spelling variations:
"su sach y thuat bao chi" » "su sach y thuat bai chi", "su sach y thuat giao chi", "su sach y thuat o chi", "so sach y thuat bao chi", "vu sach y thuat bao chi", "su sach my thuat bao chi", "su sach kxy thuat bao chi", "su sach ki thuat bao chi", "su sach y thuat bao che"
"su sach ky thuat ho chi" » "su sach ky thuat hoa chi", "su sach ky thuat o chi", "su sach ky thuat co chi", "so sach ky thuat ho chi", "vu sach ky thuat ho chi", "su sac ky thuat ho chi", "su sach ty thuat ho chi", "su sach kem thuat ho chi", "su sach kmy thuat ho chi", "su sach kkxy thuat ho chi", "su sach kki thuat ho chi"
"su xac kkxki thuat do khi" » "su xac kkxki thuat o khi", "pu xac kkxki thuat do khi", "su cac kkxki thuat do khi", "su xac kkxki thuat doi khi", "su xac kkxki thuat do thi", "su xac kkxki thuat co khi"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("su sach ky thuat ho chi") or ("su sach y thuat bao chi"))) or ("su xac kkxki thuat do khi"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("su sach ky thuat ho chi") OR ("su sach y thuat bao chi"))) OR ("su xac kkxki thuat do khi")).
• Removing quotes may allow a broader search: (((( su sach ky thuat ho chi ) or ( su sach y thuat bao chi ))) or ( su xac kkxki thuat do khi )).
• Adding a wildcard symbol may retrieve word variants: (((("su sach ky thuat ho chi") or ("su sach y thuat bao chi"))) or ("su xac kkxki thuat do khi"))*.