Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hinh tai » chinh tai, hinh thai, hinh bai
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
van cam » van nam, van lam, van cau
cam duc » cam xuc, cao duc, pham duc
van tai » von tai, van tuan
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) or (hoc sinh)) ky lang xa hoi. hieu van cam duc va ((hinh tai) or (van tai)) cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sinh)) ky lang xa hoi. hieu van cam duc va ((hinh tai) OR (van tai)) cua tu.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sinh)) ky lang xa hoi. hieu van cam duc va ((hinh tai) or (van tai)) cua tu*.