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
lanh hai » manh hai, thanh hai, lanh dao
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
nam tuc » nam thuc, nam truc, nam tu
tuc va » thuc va, truc va, tuc xa

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 xa) OR (lang xa)) hoi. hieu van nam tuc va ((lanh hai) or (lang chai)) cau triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (lang xa)) hoi. hieu van nam tuc va ((lanh hai) OR (lang chai)) cau triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang xa) OR (lang xa)) hoi. hieu van nam tuc va ((lanh hai) or (lang chai)) cau triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) OR (lang xa)) hoi. hieu van nam tuc va ((lanh hai) or (lang chai)) cau triet*.