Perhaps you should try some spelling variations:
khach cong » thanh cong, khach hang, hanh cong
hoc khach » soc khach, hoc khac, hoc nhanh
khi phong » thi phuong, thai phong, hai phong
pho thong » he thong
cong khi » cong thai, khong khi, co khi
sach tai » sach bai, sach tham, sach dao
tai thuc » thai thuc, tri thuc, dai thuc
thuc anh » thuc hanh, thuy anh, thu anh
anh khoa » doanh khoa, hang khoa
khoa pho » khoa phu, khoa khoa, khoa phau
tu lanh » tu hanh, tu lenh, tu manh
dao hoc » dai hoc, dan hoc, day hoc
su sach » so sach, vu sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu lanh dao hoc khach cong khi phong ) or ( su sach tai thuc anh khoa pho thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu lanh dao hoc khach cong khi phong ) OR ( su sach tai thuc anh khoa pho thong ))*.