Perhaps you should try some spelling variations:
lang chai » lang ha, lang cua, lang phi
cau triet » cau trieu, su triet, cua triet
hieu van » hieu va, thien van, lieu va
nam truc » nam truoc, nam thuc, nam trung
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nam tuc » nam thuc, nam tu, nam thuoc
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang x hoi. hieu van ((nam tuc) or (nam truc)) va ((lanh dao) or (lang chai)) cau triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang x hoi. hieu van ((nam tuc) OR (nam truc)) va ((lanh dao) OR (lang chai)) cau triet.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu van ((nam tuc) or (nam truc)) va ((lanh dao) or (lang chai)) cau triet*.