Perhaps you should try some spelling variations:
cam thue » cam thu, lam thue, nam thue
tang tai » hang tai, sang tao, dong tai
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
thue va » thuc va, thuyet va, thuc vat
y nang » ky nang, ly nang, v nang
va cam » va cham, va cac, va cao
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 ((tang tai) OR (dung 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 ((tang tai) OR (dung 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 ((tang tai) OR (dung 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 ((tang tai) OR (dung tai)) cuc te*.