Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
su triet » su viet, su tien, ve triet
nang xa » lang xa, nang ma, mang xa
van cam » van nam, van lam, van cau
cam duc » cam xuc, cao duc, pham duc
dan hai » doan hai, dang hai, dan khai
va dan » ca dan, va dao, va dau
hai su » hai vu, lai su, hai so

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y ((nang xa) OR (nang x)) hoi. hieu van cam duc va dan hai su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y ((nang xa) OR (nang x)) hoi. hieu van cam duc va dan hai su triet".
• Adding a wildcard symbol may retrieve word variants: thu sach y ((nang xa) OR (nang x)) hoi. hieu van cam duc va dan hai su triet*.