Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thi nang » ki nang
thi cong » tai cong, thien cong
thi hanh » thi thanh
hieu ve » hieu va, hieu van
sach ly » sach y, sach lo, sach ty
ly hang » ly quang
so sach » so sanh, bo sach, co sach
ve cac » va cac, vien cac
va hoi » xa hoi, va hoc, va hoa
ly su » ly du, ly so, ky su

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ly hang va hoi. hieu ve cac du ((thi hanh) or (((thi nang) OR (thi cong)))) ly su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ly hang va hoi. hieu ve cac du ((thi hanh) OR (((thi nang) OR (thi cong)))) ly su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ly hang va hoi. hieu ve cac du ((thi hanh) or (((thi nang) OR (thi cong)))) ly su triet".
• Adding a wildcard symbol may retrieve word variants: so sach ly hang va hoi. hieu ve cac du ((thi hanh) or (((thi nang) OR (thi cong)))) ly su triet*.