Perhaps you should try some spelling variations:
tang tai » hang tai, dung tai, sang tao
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
thue va » thuyet va, thuc vat, thuat va
va cam » va cham, va cac, va cao
y nang » ky nang, ly nang, v nang
cuc te » cua te, cuc thue, cuc tieu

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 (su sach)) y nang xa hoi. hieu va cam ((thue va) OR (thuc va)) tang tai cuc te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) y nang xa hoi. hieu va cam ((thue va) OR (thuc va)) tang tai cuc te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) y nang xa hoi. hieu va cam ((thue va) OR (thuc va)) tang tai cuc te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) y nang xa hoi. hieu va cam ((thue va) OR (thuc va)) tang tai cuc te*.