Perhaps you should try some spelling variations:
van nghiem » van nghe, van nghia, quang nghiem
hoach van » hoach va, hoach san, hoach toan
tu sach » thu sach, su sach, te sach
sach da » sach dao, sach dat, sach dau
da nghe » day nghe, va nghe, dang nghe
nghe ad » nghe adn, nghe cad, nghe ar
su pho » sau pho, su phong
mo hoc » mon hoc, co hoc
su ho » su hoa, su hoc, su co

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 da nghe ad hoc ) or ( thu hoach van nghiem ((((su ho) or (su pho))) or (mo hoc)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach da nghe ad hoc ) OR ( thu hoach van nghiem ((((su ho) OR (su pho))) OR (mo hoc)) )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach da nghe ad hoc ) or ( thu hoach van nghiem ((((su ho) or (su pho))) or (mo hoc)) ))*.