Perhaps you should try some spelling variations:
cac truc » cau truc, cac tru, cac trung
truc van » truc va, thuc van, truc ban
van dung » van dong, xay dung, tin dung
dung dai » duong dai, dung tai, dung dat
va triet » va thiet, va trien, ve triet
sach ty » sach tu, sach thu, xach tay
nang mo » nang meo, nang ma, nang co
qua cac » cua cac
mo hoc » mon hoc, co hoc
dai va » mai va

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 ty) or (sach y)) nang mo hoc. hieu qua cac truc van dung dai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach y)) nang mo hoc. hieu qua cac truc van dung dai va triet.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach y)) nang mo hoc. hieu qua cac truc van dung dai va triet*.