Perhaps you should try some spelling variations:
thien van » thi van
va triet » va thiet, va trien, ve triet
hanh tai » thanh tai, hang tai, han tai
tan hanh » tan thanh, tang hanh, toan hanh
hieu van » hieu va, lieu va, hieu ve
sach thu » sach thue, sach thieu, sach tham
sach tu » cach tu, sach ty, sach uu
soc tan » hoc tan, so tan, soc dan
tai va » thai va, mai va, tri va
x hoi » xa hoi, o hoi, x ho

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 tu) or (sach thu)) nang x hoi. ((hieu van) OR (thien van)) cham soc tan hanh tai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach tu) OR (sach thu)) nang x hoi. ((hieu van) OR (thien van)) cham soc tan hanh tai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach tu) or (sach thu)) nang x hoi. ((hieu van) OR (thien van)) cham soc tan hanh tai va triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach tu) or (sach thu)) nang x hoi. ((hieu van) OR (thien van)) cham soc tan hanh tai va triet*.