Perhaps you should try some spelling variations:
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
nang tai » tang tai, sang tai, nang cao
hang tai » hang va, dung tai
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cao duc » dao duc, cao suc, giao duc
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang xa hoi. ((hieu van) OR (thien van)) cao duc va ((nang tai) or (hang tai)) cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang xa hoi. ((hieu van) OR (thien van)) cao duc va ((nang tai) OR (hang tai)) cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang xa hoi. ((hieu van) OR (thien van)) cao duc va ((nang tai) or (hang tai)) cua te".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang xa hoi. ((hieu van) OR (thien van)) cao duc va ((nang tai) or (hang tai)) cua te*.