Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
nham thuc » nhan thuc, nam thuc, nham thu
hieu suat » hieu luat, hieu qua
thu sach » thuat sach, thuoc sach, thu hoach
xa thanh » va thanh, ha thanh, ta thanh
hieu sua » hieu qua, hieu cua, hieu su
tu sach » su sach, te sach, tu cach
doi cua » dai cua, hoi cua
thuc xa » thuc xay, tuc xa, thuc va
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thu sach)) ky nang x ho. ((hieu sua) or (hieu suat)) nham thuc xa thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang x ho. ((hieu sua) OR (hieu suat)) nham thuc xa thanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky nang x ho. ((hieu sua) or (hieu suat)) nham thuc xa thanh doi cua tre*.