Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh dai » hanh tai, hanh dao, vanh dai
tan hanh » tan thanh, tang hanh, toan hanh
sach thu » sach thue, sach thieu, sach tham
cham duc » pham duc, cham soc, pham duy
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, xach tay
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
dai su » dai sua, dai so, dan 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 ty) or (sach thu)) ((nang xa) OR (nang ma)) hoi. hieu ve cham duc tan hanh dai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) ((nang xa) OR (nang ma)) hoi. hieu ve cham duc tan hanh dai su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach thu)) ((nang xa) OR (nang ma)) hoi. hieu ve cham duc tan hanh dai su triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) ((nang xa) OR (nang ma)) hoi. hieu ve cham duc tan hanh dai su triet*.