Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thien van » thi van
hang tai » hang va, dung tai
va hang » van hang, va nang, va lang
truc va » thuc va, thuc vat, trung va
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
cuc tre » duc tre, cua tre, cuu tre

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky ((nang ma) or (sang ma)) hoi. ((hieu ve) or (thien van)) cau truc va hang tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky ((nang ma) OR (sang ma)) hoi. ((hieu ve) OR (thien van)) cau truc va hang tai cuc tre.
• Adding a wildcard symbol may retrieve word variants: thuat sach ky ((nang ma) or (sang ma)) hoi. ((hieu ve) or (thien van)) cau truc va hang tai cuc tre*.