Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh tai » thanh tai, hang tai, han tai
hanh dai » hanh dao, vanh dai, thanh dat
cam truc » cau truc, nam truc, lam truoc
truc va » thuc va, thuc vat, trung va
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
va nang » van nang, da nang, cam nang
v nang » vu nang, van nang, voi nang
ve cam » ve cham, ve cac, va cam

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