Perhaps you should try some spelling variations:
thien van » thi van
su triet » su viet, su tien, ve triet
hanh tai » thanh tai, hang tai, han tai
van hanh » van thanh, ban hanh, van anh
cham duc » pham duc, cham soc, pham duy
duc van » duc va, duc tan, duc manh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
sang ma » tang ma, nang ma, sang tao
tai su » tai so, tai tu, lai su

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 ky ((sang ma) or (nang x)) hoi. ((hieu ve) or (thien van)) cham duc van hanh tai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((sang ma) OR (nang x)) hoi. ((hieu ve) OR (thien van)) cham duc van hanh tai su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((sang ma) or (nang x)) hoi. ((hieu ve) or (thien van)) cham duc van hanh tai su triet*.