Perhaps you should try some spelling variations:
lam truoc » lam thuoc, nam truoc, lam truong
truoc va » truc va, thuoc va, truong va
hoc viet » hoc hien
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
tac ky » tac ke, tap ky, sac ky
va lam » van lam, va lap
vi hoc » li hoc, va 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 (cac ky)) ((nang xa) or (nang ma)) hoi. hieu va lam truoc va hanh vi hoc viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((tac ky) OR (cac ky)) ((nang xa) OR (nang ma)) hoi. hieu va lam truoc va hanh vi hoc viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((tac ky) OR (cac ky)) ((nang xa) or (nang ma)) hoi. hieu va lam truoc va hanh vi hoc viet".
• Adding a wildcard symbol may retrieve word variants: thuat ((tac ky) OR (cac ky)) ((nang xa) or (nang ma)) hoi. hieu va lam truoc va hanh vi hoc viet*.