Perhaps you should try some spelling variations:
chai khoa » thai khoa, chi khoa, pham khoa
chai hoi » chai thoi, cham hoi, cau hoi
kham luc » khai luoc, kham cuoc, nhan luc
te sach » toc sach
vu kham » vu khanh
dau cua » day cua, cau cua, dan cua
hieu vu » hieu va, hieu ve, hieu su
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
luc va » duc va, tuc va, loc va
va dao » ca dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky lang ((chai hoi) OR (chai khoa)). hieu vu kham luc va dao ((dau cua) or (dai cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang ((chai hoi) OR (chai khoa)). hieu vu kham luc va dao ((dau cua) OR (dai cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang ((chai hoi) OR (chai khoa)). hieu vu kham luc va dao ((dau cua) or (dai cua)) te".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang ((chai hoi) OR (chai khoa)). hieu vu kham luc va dao ((dau cua) or (dai cua)) te*.