Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu tinh » trieu tinh, chau tinh, kieu tinh
lieu tinh » trieu tinh, diep tinh, bien tinh
trung cay » trung cap, trong cay, rung cay
cong tac » cong ty
tac khan » tac nhan, cac khoan, tac chuan
khan cap » khan ap, than cap, khoan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu tinh) or (lieu tinh)) - thanh trung cay trong cong tac khan cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu tinh) OR (lieu tinh)) - thanh trung cay trong cong tac khan cap.
• Adding a wildcard symbol may retrieve word variants: theo ((chieu tinh) or (lieu tinh)) - thanh trung cay trong cong tac khan cap*.