Perhaps you should try some spelling variations:
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
van phan » van phong, van thanh, luan phan
phan tai » pham tai, nhan tai, phan thi
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
cau duc » cao duc, cau luc, chu duc
duc van » duc va, duc tan, duc manh
cuc tu » cuc du, luc tu, duc tu

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