Perhaps you should try some spelling variations:
trinh vant » trinh vat, trinh han, trinh viet
trinh van » trinh han, trinh quan, trinh toan
nang cong » nang song, dang cong, bang cong
cong manh » cong danh, duong manh, cong thanh
manh toan » thanh toan, anh tuan, tinh toan
hoc dieu » hoc thieu
toan ban » van ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc dieu) OR (hoc hien)) hanh - hanh ((trinh van) OR (trinh vant)) nang cong manh toan ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc dieu) OR (hoc hien)) hanh - hanh ((trinh van) or (trinh vant)) nang cong manh toan ban~".
• Adding a wildcard symbol may retrieve word variants: ((hoc dieu) OR (hoc hien)) hanh - hanh ((trinh van) or (trinh vant)) nang cong manh toan ban*.