Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
luc van » luoc van, luu van, duc van
vu nang » vuc nang, va nang, vu dang
hieu vu » hieu va, hieu ve, hieu su
tu sach » thu sach, su sach, tu cach
te sach » toc sach
lang xa » dang xay, lang van
lang ha » long ha
vi su » va su, ve su, ki su

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) or (te sach)) y ((lang xa) OR (lang ha)) hoi. hieu vu nang luc van hanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) y ((lang xa) OR (lang ha)) hoi. hieu vu nang luc van hanh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) y ((lang xa) OR (lang ha)) hoi. hieu vu nang luc van hanh vi su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) y ((lang xa) OR (lang ha)) hoi. hieu vu nang luc van hanh vi su triet*.