Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
truoc va » truc va, truong va, truoc bua
thuoc va » thuc va, thuoc ma, thuong va
hoc viet » hoc hien
nang xa » nang x, lang xa, nang ma
van lam » van nam
hanh va » hang va, hanh vi
tac ky » tac ke, cac ky, sac ky
va hoc » van hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((tac ky) OR (tap ky)) nang xa hoi. hieu van lam ((truoc va) or (thuoc va)) hanh va hoc viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((tac ky) OR (tap ky)) nang xa hoi. hieu van lam ((truoc va) OR (thuoc va)) hanh va hoc viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((tac ky) OR (tap ky)) nang xa hoi. hieu van lam ((truoc va) or (thuoc va)) hanh va hoc viet".
• Adding a wildcard symbol may retrieve word variants: thuat ((tac ky) OR (tap ky)) nang xa hoi. hieu van lam ((truoc va) or (thuoc va)) hanh va hoc viet*.