Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
cao xuc » cam xuc, cao duc, cao suc
xuc van » duc van, luc van, vuc van
va cao » va cac, va co, va dao
vi su » ve su, ki su, oi 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 y ((nang x) or (nang ma)) hoi. lieu va cao xuc van hanh ((vi su) or (va su)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang x) OR (nang ma)) hoi. lieu va cao xuc van hanh ((vi su) OR (va su)) viet.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang x) or (nang ma)) hoi. lieu va cao xuc van hanh ((vi su) or (va su)) viet*.